The film is shot using high-speed 3D technology, and the film’s high frame rate – 48 frames per second, as opposed to the normal 24 frames per second — has caused dizziness, nausea and headaches among some fans who saw an early screening of the movie in New Zealand over the weekend, the New Zealand Herald newspaper reported on Monday.

The film – a prequel to Jackson’s blockbuster Lord of the Rings trilogy of movies – had its world premiere in Wellington, New Zealand, on Wednesday.

In an article on the Directors Guild of America website this fall, Jackson described the benefits of increased number of frames, saying “48 frames absolutely helps 3D because suddenly you’re removing a substantial amount of the motion blur that you get at 24 . Your eyes get a much smoother experience.”

“Even though I’ve made a lot of fantasy films, I’ve always tried to make them as realistic as possible,” Jackson explained.

Some fans found the realism hard to absorb, particularly for close-up shots, the Herald reported.

“You have to hold your stomach down and let your eyes pop at first to adjust,” tweeted one fan.

The Hobbit isn’t the first film to have caused sickness among viewers.

James Cameron’s hit, Avatar, also drew some complaints, as did birth scene in The Twilight Saga: Breaking Dawn.

Those complaints didn’t hurt those films’ box office takes. Avatar is the top-grossing film in movie history, with a worldwide take of $2.78 billion, according to the website Box Office Mojo.

Breaking Dawn has made $702.3 million worldwide, the website estimates.